Prior art "bubble-sort" elements are known that compare the magnitudes of two input signals and throughput the signal of lesser magnitude to a "low" output and throughput the signal of greater magnitude to a "high" output. When there is only one input signal, it is throughput to the "high" output since it is of greater magnitude than the other input, which is null. Thus, the output to which a particular signal is throughput may be affected by the presence of another input.